Carton



Aug. 1, w39.

Filed April 29, 193e g INVENTCnfe U @120e W paw Patented ug. l, 1939 UNITED STATES aleman CARTON Clarence W. Vogt, New York, N. Y.,

Ilslsncr. by

mesne assignments, to Owens-Illinois Glau- Conxlall'y. Toledo,

Ohio, a corporation of Ohio Application April 29, 193B, Serial No. 76,898

type in which the closure is formed by foldabley and interlockable flaps.

- One object is to provide a carton having a new and improved form of closure naps which may be.

.interlocked by merely pressing into and slightly beyond final closure position.

Another object is to provide closure iiaps which when interlocked will effectively withstand diagonal compressive forces incident to ordinary handling, and which will prevent collapse of the carton and snapping of said flaps outwardly into open position. v

A further object is to provide a carton-having new and interlockable closure flaps adapted to eiectively withstand internal pressure such as that due to the weight of the material in said carton, tending to bulge said flaps outwardly into open position.

The important features of the invention will be apparent from the following description of one embodiment and fromy an inspection of the accompanying drawing in which: v Figs. 1-5 are perspective views of the lower end of a carton shown in inverted position, and showing respectively the bottom closure flaps in successive phases of being folded into interlocked position, Y Fig. 6 is a section through the lower end of a carton after the closure flaps have'be'en interlocked, and the carton turned into its normal upright position and filled, and

Fig. 'l is a plan view of the bottom portion of the blank 'from which vthe carton shown in Figs. 1-6 is constructed.

The carton in the specific form illustrated is constructed lfrom a blank made of comparativelyl rigid material such as cardboard, and having a series of longitudinally extending scoreV or crease lines II along which the blank is folded to form the side walls I2 of the carton. One side of the blank may be provided with the usual comparatively narrow side flap adapted to be adhesively secured to the opposite side of the blank to form g ner along the crease or score lines Il extending together or directly abut when these flaps have been folded inwardly across the end of thecarton as shown in Fig. 2. To permit these inner flaps I4 and I! to be interlaced with the outer naps, they are each provided with a crosswise slit or incision 20 extending substantially parallel to the score line I8, and a second slit 2| extending substantially at right angles to the slit 20 and forming therewith a flap section 22. This flap section 22 may be deflected out of the plane of the main body of the inner flap to form a gap along the slit 20 sufiiclently wide to permit the easy insertion therethrough of a side portion of the outer flap I6. The angular slits 2l and 22 on the two inner flaps I4 and I5 are so arranged that when said aps are folded inwardly across the open end of the carton, two slits 2l will be in alinement and the two flap sections. 22 will be in symmetrical relationship as shown in Fig. 2.

'I'he outer flap I6 has its side edges convergingfrom the score line` I8 along diagonal lines to form a base portion 26'01' a length substantially equal to the distance between the slit 2l and the adjacent edge of the flap I4 or I5 and beyond this baseportion there is a tongue 25. The base portion and the terminal portionh of the tongue have widths equal to or slightly less than the distance between the two slits 20 when the inner iiaps are in closure position.

On opposite edges of the tongue 2 5 there are provided a pair of opposed side extensions in the form of tabs 21 adapted to be inserted respectively in the slits 20, there being a pair of opposed notches 28 at the sides of lthe tongue beyond said side tabs 21 to form the end of the tongue as an end tab 30.' l

The outer flap I1 is provided with a base portion 32 tapered towards its outer end similar to the base portion 26, and beyond this base portion there is a tongue 33 having a maximum width substantially the same as the width of the tongue 25, that is slightly less than the distance between the slits 2U of the two inner flaps when said ilaps are foldled inwardly in closure posinon. The nap n/differs from the flap ls primarily in that it does not have any side tabs.

In order to interlock the flaps of the carton. they must, be deflected inwardly of the carton. This folding and interlocking operation is difcult unless the carton is empty or there is room for this inward deflection of the flaps.' For that reason my improved.v closure flaps arev shown applied to the, bottom of the carton. However. as far as certain aspects of the invention are concerned, similar closure members may be prois not intended to be filled to the top.

With the opposite sides of the blank adhesively secured together to form a tubular body open at both ends, it is held as shown in Figs. iso that the flaps are readily accessible. In Fig. 1 the flaps are showniin open position ready to be folded and interlocked. The folding and interlocking of these aps is started by folding inwardly the two flaps I4 and I5 across the open end of the carton, as shown in Fig. 2. The flap I1 is then folded over the inner flaps I4 and I5 and pressed downwardly as shown in Fig. 3 so that the two inner flaps Il and I5 are deflected towards the interior of the carton and the flap sections 22 are deflected inwardly with respect to the main body of said inner flaps to form a gap along the slits 20. By providing the flap I1 with a tapered base portion 32, the oblique side edges of this base portion will serve more effectively to bend the two inner flaps Il and I5 downwardly in the interior of the carton as shown in Fig. 3.

While the flap I1 is held against the two inner flaps I4 and I5 by a finger as shown in Fig. 3, the other outer closure flap I5 is pressed downwardly until the side tabs 21 reach the slits 20. By further pressure the tabs will snap through gaps formed along the slits 20 as shown in Fig. 4. By providing the outer flap IB with a tapered base portion, the inward folding of this ilap is facilitated. l

Since the two inner flaps I4 and I5 are held downwardly by/tl'ie outer closure ap I1, the inward folding of the other closure flap I6 in the position shown in Fig. 4 will not subject the I,side tabs 21 to any excessive bending stresses tending to crease said side tabs.

After the side tabs 21 of the outer flap I6 have been snapped through the slits 20, the ilnger pressure on the'two flaps I6 and I1 is released to permit all of the flaps to rise into the position shown in Fig. 5. In this position, the end tab 3l) will extend slightly above the plane of the two inner flaps I4 and I5 so that any diagonal compression on the carton incident to ordinary handling will cause either one or the other side edge of said end tab, as well as the side edges of the tongues 33, to abut the inwardly facing edge of its corresponding slit 20, thereby effectively preventing the flaps from snapping outwardly into open position, and preventing diagonal collapsing of the carton.

The outer closure flap I1 serves not only to deflect the two inner flaps I 4 and I5 inwardly during the folding and interlocking operation, but also serves to deflect the end tab 30 outwardly beyond the plane of the inner -ilaps I4 and I5, due to the inherent tendency of said flap I1 to bend outwardly along its crease line I8.

In Fig. 6 is shown the carton after its bottom flaps have been interlocked, the carton turned into its upright position, and the interior thereof illled. 'I'his carton is adapted to be filled with any suitable material and is shown in conjunction with an inner expansible bag 35 `made of thin flexible material and containing a suitable liquid. This bag may be permanently secured to the carton or may be detachable therefrom. The pressure of the fllled bag 35 against the bottom closure ilaps serves to bulge these flaps slightly outwardly when the carton is lifted from a supporting surface, as shown in Fig. 6. This bulging serves to more effectively deflect the end tab 30 outwardly beyond the plane of the inner flaps Il and I5, so that the use of the side edges of this end tab for effectively withstanding diagonal compression on the carton, is assured.

At the central portions of the bottom flaps, where the greatest bulging of the carton takes place, there are three overlapping flap sections4v which, due to the frictional contact therebetween, will effectively prevent the flapsv from bulging outwardly to any extent sufficient to snap the flaps into open position. These three overlapping sections are the flap sections 22, the tongue 33 and the tongue 25. Furthermore, the internal pressurel of the filled carton against the flap section 22 serves to'close the slits 20 and to effectively hold the side tabs 21 therein.

'Ihe end tab 30 is shown with parallel sides. but may be flared inwardly towards its base to form side ears adapted to overlap the slits 2li.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A carton having four flaps at one end, two

of which are adapted to form the inner opposed closure vflaps and the other two the outer opposed closure flaps, said inner ilaps each having an L- shaped slit with one portion disposed substantially parallel to the base of the ap and another portion extending to the end of the flap, one of said outer flaps having side tabs adapted to be inserted through said slits to interlock said latter flap and said inner flaps when in carton closure position, the other outer ap being provided with a tongue at its outer end having a maximum width substantially equal to the distance between said slits when said inner naps are in said carton closure position.

2. A carton having four foldable extensions at one end, two of said extensions being adapted to form the opposed inner closure flaps and the other two the opposed outer closure flaps, each of said inner flap extensions being provided with an edge extending substantially parallel to its fold line and spaced inwardly from the outer end of said inner flap, one of said outer ap extensions having side tabs adapted to extend along the inner surfaces of said inner flaps, and outwardly beyond said edges. the outer end of said last mentioned outer flap having a tab the width of which is not materially less than the distance between said edges, the sides of said end tab being adapted to abut said edges when all of said flaps are in carton closure position.

3. A carton having at one end a pair of opposed inner closure aps and a pair of opposed outer closure flaps, each of said inner flaps being provided with an edge extending substantially parallel to its fold line and spaced inwardly from its outer end, one of said outer ilap'having a tongue including a pair of side tabs and an end tab extending outwardly beyond said side tabs, said side tabs being adapted to extend on the inner sides of the inner flaps beyond said edges, and the sides of said end tab being adapted to abut said edges to withstand the diagonal compression on said carton when all of said aps are in closure position.

4. A carton having at one end a pair of opposed inner closure flaps and a pair of opposed outer closure naps, each of said inner closure ilaps being provided with a crosswise slit ex'- tending substantially parallel to the fold line of said latter flap, and another slit extending substantially at right angles to said ilrst mentioned slit, said angular slits defining a flap section adapted to be deflected out o! the plane of the moin loods' oi seid lutter inner flop, one oi* said i outer naps nui/ing o. tongue ot its outerend iormed with n poir oi side tubs, und on end telo eirtendinu beyond seid side tutos, the other elosnre non being provided with s tongue ut its outer end nuving er nonidniun'i width substontiolir eouol to the distance between the orosswise slits oi sold inner Hops when in closure position, soid istter tonuue ioeing adopted to overiop tine outer surfaces oi? seid p sections, und the other rst mentioned tongue ioeine adopted to overlop the outer surface oi' the second mentioned tongue, with the side tabs oi said irst mentioned tongue extending through said crossvrise slits and along the inner surfaces of said inner flaps.

5. A carton having at one end at pair oi' opposed inner closure flaps and a pair of opposed outer closure Hops, euch oi' said inner closure flaps being provided with a, crosswise slit extending substantially parallel to the fold line o! said latter ildp, and another slit extending therefrom to the end of tile flap and et right ongles to said iirst mentioned slit, seid angular" slits defining a flap section adapted to be deiected out of the piene oi the main body of sold letter inner ep, one of seid outer iaps having a. pair oi" side tabs, tire other closure naps being provided with a tongue ot its outer end lying between the crosswise slits ot said inner flaps and having side edges parallel with and closely adjacent to said crosswise slits, said tongue overlapping the outer surfaces oi said dup sections, und the nop inevine said side tots overlapping the outer sui-ieee oi seid tongue, with the side tubs extending through seid erosswise slits und nionu the inner surfaces of Suid inner nous.

6. it norton inn/ine ut one end n poir oi opposed inner closure tions ond e noir oi opposed outer closure naps, each of seid inner eiosure naps being provided with o crosswise slit extending substantiolly parallel to tine i'old line of said letter flap, one of said outer ilaps having a tongue at its outer end formed with a pair oi.' side tabs., and an end tab extending beyond said side tabs, the other closure flap being provided with a tongue at its outer end having a maximum width substantially equal to the distance between the crosswise slits of said inner iiaps when in closure position, said latter tongue being adapted to overlap the outer surfaces oi said inner flaps, and the other first mentioned tongue being adapted to overlap the outer surface of the second mentioned tongue, with the side tubs of seid rst mentioned tongue extending through said crosswise slits and along the inner surfaces of said inner iiops.

CLARENE W. VOGT. 

